Field
This invention relates to vibration reduction assemblies for fan blades and, more particularly, to a two-piece vibration isolation assembly for use in a ceiling fan.
Description of the Prior Art
It is generally known in the ceiling fan industry that blade vibration is undesirable, causing an unacceptably high level of noise to emanate from the blades during operation. While a certain amount of vibration is unavoidable, it has been found preferable to minimize the amount of vibration transmitted from the motor to the blades in order to effect smooth, quiet operation. Accordingly, some type of vibration isolation system is commonly employed to reduce the transmission of vibration from the ceiling fan motor through the blade irons to the blades.
Two known prior art references disclose the use of vibration dampers composed of rubber, or a similar elastomeric compound, disposed between the base of the blade iron and the fan motor. U.S. Pat. No. 4,850,799, issued Jul. 25, 1989 to Bucher, et al., discloses a two-part "rubber fly wheel" having a rigid core formed from steel. U.S. Pat. No. 4,511,310, issued Apr. 16, 1985 to Pearce discloses a similar device comprising a rigid ring having elastomeric inserts. Both the Bucher et al. and Pearce devices are fastened to the rotor of the fan motor by a plurality of screws, prior to attaching the blade irons. While these devices may be effective, they add unnecessary cost to the fan and increase the complexity of the installation and/or assembly.
It is also known to insert an elastomeric grommet into the mounting hole of a conventional ceiling fan to isolate the blade from the blade iron. Such grommets typically comprise a tubular center section with an annular shoulder at each end. Installation of such grommets requires deforming one end thereof, including the shoulder formed thereabout, for insertion through the blade mounting hole. If the grommet is not properly installed, its effectiveness in reducing vibration is destroyed, or at least severely compromised.